Question

Negative staining method is used for examining very small objects. It is generally used in \(\underline{\hspace{2cm}}\)

• A. TEM
• B. SEM
• C. Confocal Microscopy
• D. ESEM

Hint:

Think "negative" means staining the background, not the object itself. This method is perfect for seeing the outline or silhouette of tiny things like viruses, and it requires the "through-the-sample" view of a TEM.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
The question asks to identify the type of microscopy for which the negative staining technique is primarily used.

Step 2: Detailed Explanation:
Negative staining is a sample preparation technique where a specimen is suspended in a solution of an electron-dense material, such as uranyl acetate or phosphotungstic acid. When dried, the heavy metal stain forms a dark background around the much lighter, unstained specimen. This creates a high-contrast image that reveals the size and surface morphology of very small objects like viruses, bacteria, or macromolecules. Because this technique relies on the differential scattering of electrons passing through the stained background versus the unstained sample, it is a method used for Transmission Electron Microscopy (TEM).
\[\begin{array}{rl} \bullet & \text{SEM and ESEM visualize surface topography and do not use negative staining. } \\ \bullet & \text{Confocal Microscopy is a type of light microscopy that uses fluorescence and is not related to this staining method. } \\ \end{array}\]

Step 3: Final Answer:
The negative staining method is generally used in TEM (Transmission Electron Microscopy).